var cats = PerformanceCounterCategory.GetCategories();

        foreach (var cat in cats)
        {

            var names = cat.GetInstanceNames();

            if (names.Any(i => i.ToLowerInvariant().Contains("w3wp")))
            {
                Console.WriteLine(cat.CategoryName);
            }
        }



        private static string GetProcessInstanceName(int pid)
        {
            PerformanceCounterCategory cat = new PerformanceCounterCategory("Process");

            string[] instances = cat.GetInstanceNames();
            foreach (string instance in instances)
            {

                using (PerformanceCounter cnt = new PerformanceCounter("Process",
                     "ID Process", instance, true))
                {
                    int val = (int)cnt.RawValue;
                    if (val == pid)
                    {
                        return instance;
                    }
                }
            }
        }